21281720

素因数分解:

$2^3\times 5^1\times {\mathrm{443}}^1\times {\mathrm{1201}}^1$

素因数の和:1655

約数の個数: 32

約数和(自身を含む): 48031920

約数和(自身を除く): 26750200

約数列:

[1, 2, 4, 5, 8, 10, 20, 40, 443, 886, 1201, 1772, 2215, 2402, 3544, 4430, 4804, 6005, 8860, 9608, 12010, 17720, 24020, 48040, 532043, 1064086, 2128172, 2660215, 4256344, 5320430, 10640860, 21281720]

約数ペア:

[(1, 21281720), (2, 10640860), (4, 5320430), (5, 4256344), (8, 2660215), (10, 2128172), (20, 1064086), (40, 532043), (443, 48040), (886, 24020), (1201, 17720), (1772, 12010), (2215, 9608), (2402, 8860), (3544, 6005), (4430, 4804)]